Irreversible circuit

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In the study of reversible computing, an irreversible circuit is a circuit whose inputs cannot be reconstructed from its outputs. Such a circuit, of necessity, consumes energy. More precisely, there is a lower bound derived from quantum physics on the minimum amount of energy needed for each computation with such a circuit. In contrast, reversible circuits can, theoretically, be designed to operate on arbitrarily small amounts of energy. [1]

Any irreversible circuit can be simulated by a reversible circuit that is padded with additional outputs. [2]

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References

  1. Landauer, Rolf (1961), "Irreversibility and heat generation in the computing process", IBM Journal of Research and Development, 5 (3): 183–191, doi:10.1147/rd.53.0183, MR   0134833
  2. Bennett, Charles H. (1973), "Logical reversibility of computation", IBM Journal of Research and Development, 17 (6): 525–532, doi:10.1147/rd.176.0525, MR   0449020